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<p>
This page is part of the <a href="spec_1.53E.jsp">DAS 1.53E specification</a>
</p>

<h2>maxbins - restricting the maximum number of features</h2>

<p>
A DAS client can do a <a href="http://www.biodas.org/documents/spec.html#features">standard DAS - features</a> request and add the parameter 
 <pre>
 
 maxbins=X
 
 </pre>
 where X is the number of pixels used for display on the DAS client. 
 </p>

<p>
One of the core principles behind DAS is that the servers are rather simple, whereas all intelligence
is located on the DAS client side, which manages to provide a clever integration of the data obtained from various DAS servers.
 The <strong>maxbins</strong> extension adds a bit of intelligence to the DAS server side, for performance reasons with large number of features. 
 </p>
 
 <p>
 This extension is useful for DAS servers that return <b>large numbers of features</b>. The maxbins parameter
 gives the server an idea of how big the display on the client side will be and then can choose
 the right resolution for the returned features. If a whole chromosome is being displayed it does not make
 sense to reply thousands of features of size 1 base. Instead the server might group features together, show
 only the features with the highest scores. The scaling is depending on the actual biological data, hence
 DAS should not enforce a certain behaviour regarding that.
 </p>
 
 <p>
 Ensembl adds the <strong>maxbins</strong> parameter by default to all DAS requests.
 If a server does not support this parameter, it should simply respond with all features for the requested segment.
 </p>
 
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